OBJECTIVES: a. Overall objectives. Our overall objectives in studying thalassemia, hemoglobinopathies and related problems are: (1) To examine the genic defects and their results. (2) To study results of interaction of various genes. (3) To study results of interaction between genes and environmental factors. (4) To study cellular and organ pathology occurring from the above processes. (5) To study clinical manifestation. (6) Try to understand the magnitude of effects on the population. (7) Use the information for teaching-training health personnel and for guidance in an attempt to improve health of the people. b. Goals set for the current year. In addition to continuation of the usual clinical, hematologic and formal genetic studies, specific goals include: (1) Structural identification of some new hemoglobins. (2) Globin synthesis study in certain thalassemia genotypes. (3) Start the analysis of clinical and hematologic data in approximately 1,000 beta-thalassemia/Hb E patients. (4) Evaluate susceptibility to infectious diseases of thalassemic patients. (5) Study the effect of the new iron chelating agent, 2, 3-Dihydroxybenzoic acid in thalassemic patients. (6) Continue the study on immunologic diagnosis of alpha-thalassemia. (7) Continue pathologic evaluation of dead cases of thalassemic patients.